Printhead Driver Circuit - Epson Stylus COLOR 1520 Service Manual

EPSON Stylus COLOR 1520

2.3.2.5 Printhead Driver Circuit

This printer has 2 separate printhead driver circuits:for the black head and for the color head. Each
circuit has the common voltage driver circuit attached to the MAIN board and the nozzle selection circuit
attached to the head driver circuit board. The common driver circuits for the both black and color heads
are composed of the hybrid ICs (IC19) and the terminal transistors. 128-bit transfer gate array IC
IR2C72C is used for the black head nozzle selection circuit and 128-bit transfer gate array IC IR2C72C
(for cyan and yellow) and 64-bit transfer gate array IC IR2C73C (for magenta) are used for the color
head nozzle selection circuit. Printing data is separated into the common voltage signal and the nozzle
selection signal at the gate array E05B33 (IC6) and is then transferred to the corresponding circuit.
Figure 2-24 shows the printhead driver circuit block diagram.
E05B33 (IC6)
BCHG,BKC
BND0/1,BMD0/1
SBDATA
BHCLK
BHLAT
BA/BHDATA
BHNCHG
VHPR
SCLK,SSTB,SCLR
CCHG,CKC
CND1/2,CMD1/2
SCDATA
CHCLK
CHLAT
YHDATA
CHDATA
MHDATA
CHNCHG
C211 MAIN Board
2-24
Common Driver
Common Driver
Figure 2-24. Prinrhead Driver Circuit Block Diagram
IR2C72C
COM
CLK
LAT
SI
NCHG
VHV
IR2C72C
COM
CLK
LAT
S3
S1
NCHG
VHV
IR2C73C
COM
CLK
LAT
S2
VHV
Head Driver Circuit
Black Head
Cyan
Yellow
Magenta
Rev. A